Many back injuries are sustained when someone has to pick up or place a relatively heavy object either from, or on the floor. This is particularly so if the lifting or placing has to be done repeatedly.
Many such objects or items are transferred from a truck, for example, to a customer, or sometimes to or from a warehouse. A two wheeled dolly or cart known as a hand truck is often used for such purposes. For example, a beverage distributor will remove cases or kegs from a truck and stack them one at a time on the projecting shelf at the bottom of the cart and build a stack. When the cart is full the stack is tilted back and wheeled into a customer's business, for example, usually to be stacked again in a storage area. The case at the top of the stack is the easiest to place or transfer because it can be moved or placed without bending over.
It would accordingly be desirable if a cart or dolly could be provided where the stack on the cart or dolly is formed on or removed from the cart without bending over.